TIC Area

Integrate a total-ion chromatogram using trapezoidal area.

Description

Chromatogram area integrates signal over time, while peak intensity reports the largest sampled value.

Chromatogram area integrates signal over time, while peak intensity reports the largest sampled value. Unequal sampling intervals can be handled by trapezoidal integration.^[1]

Integrate a total-ion chromatogram using trapezoidal area.

When to use TIC Area

Use this tool to integrate a total-ion chromatogram using trapezoidal area.

Prepare the measured profile, formula counts, upstream model outputs or caller-defined reference criteria requested. Keep paired entries aligned and units, sample basis and preprocessing consistent.

How to use TIC Area and understand its results

Prepare the measured profile, formula counts, upstream model outputs or caller-defined reference criteria requested. Keep paired entries aligned and units, sample basis and preprocessing consistent.
Enter timesMinutes, totalIonIntensities using the field table and calculation rules, then run the tool.
Read area, peakIntensity. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
timesMinutes	Times minutes	list of number	Required
totalIonIntensities	Total ion intensities	list of number	Required

Enter at least two aligned strictly increasing times in minutes and nonnegative intensities. Return area in intensity×minutes and maximum sampled intensity.

area=Σ(time_i−time_(i−1))×(signal_i+signal_(i−1))/2

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
area	Area	number
peakIntensity	Peak intensity	number

json

{
  "input": {
    "timesMinutes": [
      0,
      1,
      2
    ],
    "totalIonIntensities": [
      0,
      10,
      0
    ]
  },
  "output": {
    "area": 10,
    "peakIntensity": 10
  }
}

Limitations and assumptions

No baseline correction, peak boundaries or interpolation beyond linear trapezoids is provided.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use TIC Signal Normalization: Scale a peak-area vector to a supplied total ion current. For a complementary task, use Peak FWHM: Interpolate chromatographic full width at half maximum.

References

TIC Area — tool.io

Similar or alternative tools

TIC Signal Normalization
Scale a peak-area vector to a supplied total ion current.
Peak FWHM
Interpolate chromatographic full width at half maximum.